气升式环流反应器的流体动力学模型

用空气-水体系,在下降管直径和上升管直径分别为0.03m和0.09m,反应器的总高度为1.3m的气升式环流反应器中对气含率和流体循环速度进行了实验研究,总结了液体速度和气含率随表观气速的变化规律;根据动量平衡原理和漂流通量模型建立了气升式环流反应器中液体循环速度和气含率间的理论关系式,给出了各局部阻力损失系数的计算方法,并对这些阻力损失系数和分布参数进行了计算,实验结果表明,气速小于0.065m*s-1时,气含率与下降管液体速度随气速的增加明显增加,在实验气速范围内,总阻力损失系数与气速无关,其值为3.75.模型计算表明,循环液速和气含率的预测值与实测值的平均相对误差分别为3.6%和0.29%.

Hydrodynamics in an Air-Lift Loop Reactor

Liquid circulation rate and gas holdup in an air-lift loop reactor were experimentally investigated as changing with the superficial gas velocity for the system of air-water. Relationships between gas holdup and liquid circulation rate were established on the basis of the momentum balance and the drift-flux model, the method of determining local frictional-loss coefficients was introduced, and the coefficients and the distribution parameter were calculated. The result shows that when the gas velocity is less than 0.065 m/s, the gas holdup and the velocity of liquid in down tube increase as the gas velocity increases. In the experiment gas velocity range the total frictional loss coefficients are not related to gas velocity and its value is 3.75. The calculation result by this model shows that related errors of liquid rates and gas holdup between calculated value and their experimental data are 3.6% and 0.29% respectively.